Phineas and Ferb: The Phineas Legacy
by APersonOfManyNames
Summary: Back in the world that he left behind because he couldn't forgive himself, Phineas Flynn, aged 18, will have to contend with the bane of his existence, Thanos, to save his younger self and all others he lost. All the while, the younger Phineas must deal with the fear of becoming like his other-self. Can things ever return to the way they used to be? Find out in this epic finale!
1. Prologue

Prologue

Phineas Flynn stands in a clearing with desert-dry dirt at his feet while a gentle breeze smacks his exposed face. Stars sprinkle the sky. He looks over his shoulder at the outline of a ten year younger, more lively city–glistening like a beacon. The soothing cool breeze flows past his face as he faces forward. A blade extends from his black and yellow suit. The amor retracts from one of his hands, he then presses the blade against the bare skin.

He winces as crimson blood drips down onto a patch of dirt, and seeps into its crevices. Suddenly, wind blasts his exposed face, at once the armor forms over his face and his blood-soaked hand. An average looking man wearing a suit, appears in front of Phineas.

"Blackheart I presume?" Phineas speaks.

"What is this? Formality?" Blackheart laughs in a guttural voice.

"Mephisto sent me." Phineas sighs.

"Ah, my father no doubt wishes Thanos dead."

"As do I, so, where is he?" Phineas asks.

"He's imprisoned in a place called the Raft." Blackheart tells him.

"I know the place..." Phineas says, Blackheart disappears at once. Wasting no time, Phineas flies off.

_The Raft_

Thanos stands against the back of his cell, his void-like eyes stare at his shallow reflection in the translucent cell walls. They lock onto a small misshapen section of his armor near the center chest area. He clenches his fist tight, grimacing vibrantly. He hears a slight buzzing sound, the area beyond the cell becomes visible, a solid stone wall around it creates a narrow path sandwiched between the two. The single door opens, a man decked out in armor akin to swat gear, walks in. In his hands, a single tray of paste food that he presses against the front of the cell. It is absorbed into it, and thuds on the ground. Bits of the slop splatter on the floor.

"Hope you're hungry." The guard says,  
"Tell me…" Thanos mutters, in his deep, commanding voice.

"Wha...what?" The guard mumbles, stopping in his tracks.

"Do you ever wonder what you'll be remembered for when you die?" Thanos asks.

"What kind of question is that." The guard takes an unnoticed step back.

"I'll know what I'll be remembered for, because I'll carve it into the very being of those who dared to defy me!" Thanos smiles as the guard hastily leaves.

Meanwhile, Phineas approaches The Raft. He stops, hovering in the air, swiftly spotting a helipad. He lands there, a massive door opens, revealing a hanger with a variety of helicopters strewn about, and an unmissable flurry of guards running out with rifles in tow. Phineas puts his hands up. Taking a gulp of air, he retracts his helmet. At once, they lower their guns.

"It's you, didn't realize, should of, the outfit is almost identical. Guess I know who you're here to see." A guard speaks up, walking past the other men.

"Yes." Phineas says, glancing around at the guards.

"Very well, come with me." The guard says. They start walking together.

"So, bright upstarts–in Danville of all places, what made you want to start taking on the bad guys?" The guard asks.

"It just sort of happened..." Phineas bites down on his teeth, letting out a pestered sigh.  
"Ah, one of those types. So, been wondering, what's with the kids who looked just like you older ones? When all of you walked in with The Mad Titan himself, I couldn't believe how similar you guys were. But I was so caught up I never thought to ask. What's the relation?" The guard innocently inquires. Phineas lets out an extended sigh, followed by a huff.

"Sorry, didn't mean to bring up a bad topic." The guard says, Phineas nods, as they continue the rest of their trip.

They stop before a brick room. A singular door for entrance and exit.

"He's just through here. Sure your up for it?" The guard inquires. Phineas looks down at his hand, shaking, he bites his lower lip.

"Yeah...yeah..." Phineas reaches for the door handle, his hand trembling viciously as he twists the knob. The bolt clicks. Phineas opens the door and steps in, his eyes keep to the ground.

Thanos stands up immediately. He dares to look up at Thanos, who stares back at him with inquisitive eyes and a tilted head.

Thanos shakes his head as he looks down at the ground. "Can't be, if you weren't gone, I wouldn't have made it a few steps in this world before you made your presence known..."

Thanos stands up, towering over Phineas, he gets as close to him as the cell allows.

"I want to see your insides plastered on these walls...so bad..." Phineas's voice shakes as every facet of his being coils.

"It is you...should have known from that look in your eyes." Thanos says, grinding his teeth.

"A month of hell isn't good enough for you..." Phineas growls.

"Now now," Thanos says, "I can't get out of here anymore than you can get in here."

"You'll find a way, and that I can't allow." Phineas says.

"I will, but you can't stop me. Because unlike last time, I wanted you to plunge that sword through me. Now, I want nothing more than to destroy everything you tried so desperately to build up." Thanos says.

"You won't get that chance..." Phineas clenches his fist.

"Oh, but I've already started..." Thanos smiles.

"What are you talking about?!" Phineas shouts, his leg twitching forward.

"Oh, I just told them all about you, from the death of all you hold dear, to your would-be baby." Phineas yells, punching the cell.

"And Isabella, well, she didn't think I was all that bad…" Thanos smiles while saying this. Phineas storms out of the room, slamming the door shut. He presses his back against the wall, his breathing, fast and uncoordinated. Thanos puts his hand on the cell, they start to develop of a hue of energy. The guard looks at Phineas.  
"What's the matter with you?"

The cell and the stone walls surrounding it blast out. Phineas's helmet automatically forms over his face. He's thrown forward, a stray stone shard pierces through the side of the guard's head. Phineas skids on the floor as it collapses beneath him, falling to the next floor down, rubble piles on top of him.

Thanos walks out as he brushes off debris. He looks to his right and charges full speed ahead. Several guards run in, the moment they hold up their guns, they are smashed by a giant backhand. Thanos grabs one by the head and throws him into a wall. Thanos keeps running, stopping when he reaches the hanger, several helicopters, and an open hanger door. Several more guards rush him, he simply crushes them.

Thanos spots a helicopter starting up, he smashes the pilot door, gripping the pilot to death, he tosses the corpse out and gets in. The seat and control panel creaking, he lifts off. He goes full throttle with it, out of the hanger and speeding through the air.

Phineas's eyes snap open. He smashes through the rubble; flying up immediately, he looks around. Seeing the guard on his side, blood pooling from him as the shard sticks up out of his head. Phineas rushes to the heliport. He looks, a single missing helicopter, and a trail of bodies.

"Nooooo!" He lets out a shout that boils his entire body, every fiber of his being engaging in pure fury. His thoughts race, from reasonable assumptions straight to impossible scenarios. He flies out at once, his heart racing faster than the fastest he could ever hope to go.


	2. Chapter 1

**Welcome to chapter 1 of my newest story, my previous story was a leap in judgement on my part, and as such, I am halting that for the foreseeable future, and continuing the story of "Phineas and Ferb: The Thanos Objective" with the third and final installment into the series. It will be my biggest project yet, and I can not guarantee a new chapter every week, but if you like it, you can always get notifications for when the new chapter arrives. Without further ado, enjoy!**

Chapter 1

(A day ten years in the making)

The sun beating down upon their faces, and tranquil green grass below them, Phineas and Ferb rest their backs against the big tree in their backyard. A light-brown fence with a single gate acts as its border. Looking towards the bright-blue sky, Phineas sees a bird soar gracefully through the air. A flutter of inspiration takes him, but it quickly dissipates; deciding to keep his back against the tree, Phineas says,

"I don't know what to build today. We could...ugh."

"Well how about..." Ferb begins speaking. The gate opens to the backyard, Phineas and Ferb see, wearing a pink pleated skirt atop a plain white shirt, Isabella walking in.  
"Whatcha doin?" She asks, looking at Phineas.

"Hey, nothing much. Haven't come up with anything." Phineas says, shrugging his shoulders. Putting his head back against the solid bark.

"Oh. Well...would you...like to help me look for a few discarded items at the carnival?" Isabella sheepishly leans forward with a smile, clasping her hands together. Phineas gives her a blank stare. Realizing what she meant, he gives a proper response,

"oh, sure, I suppose we shouldn't leave those. Come on Ferb" Phineas pushes himself off the ground, Ferb trails behind as they leave the rigid confines of the fenced-in backyard.

A block down, their small legs still invigorated, they happen upon two familiar people.  
"Where're you guys off too?" Buford asks, Baljeet who is standing off to the side, looks at them with timid intriguement.

"We're going to the carnival to collect a few things, want to come?" Isabella offers.

"Sure. Why not, sounds fun." Buford says.

"Great, most of the Fireside girls are already there." Isabella tells him.

_Flynn-Fletcher home_

Stacy, sporting a turquoise shirt, a blue skirt, and bow in her hair, sits on a chair with her fists against her hips. She looks towards a single bed, where Candace sits up against the back frame, twiddling with her orange hair.

"So, not going to bust your brothers today, really?" Stacy interrogates.

"What's the point anymore. Doesn't seem right after what we've been through."

"I suppose, I mean, those were some pretty intense times." Stacy says, looking out the window.

"I'd say."  
"Besides that...you're brothers aren't even in the backyard." Upon hearing that, Candace shoots up off her bed and runs up to the window.

"Where'd they go!?" Candace shrieks.

"Dunno." Stacy shrugs.

"We gotta find them." Candace says, rushing out of her room. Stacy follows, her legs ache as she tries to keep up. They haul their rears down the sidewalk to the left immediately after leaving the house. "Now where would they have gone?" Candace says to herself. Stacy gets side by side with her. Hearing the pattering of feet by her side, Stacy looks down.

"Hey sis." Ginger says, looking up at her. Wearing an orange uniform with a brown skirt.  
"Ginger, what are you doing here?" Stacy asks. 

"I was told to meet Isabella and the rest of the Fireside Girls at the amusement park. You remember the one, right?" Ginger asks.

"Yeah…" Stacy shoots a look at Candace. "We know where they're heading can we slow down?!"

Candace stops in her tracks. Breathing in and out and in some more, Stacy leans on Candace.

"Come on Stacy, we have to go get them." Candace says, walking now.

"Yeah yeah." Stacy grumbles.

"What's the matter Stacy?" Ginger asks as they keep walking.  
"Nothing, Ginger, I'm fine."

"Oh come on, you can't be that exhausted." Ginger says.

"It's not the run!" Stacy simmers. Ginger stops in her tracks, followed by Candace.  
"Well, then, what is it?" Ginger inquires. Stacy ignores her, opting to look straight ahead, and to keep walking. Candace and Ginger following suit.

They arrive at the amusement park, bustling with tons of lively people.

"Oh come on, it's not like this place wasn't just totaled!" Stacy throws her arms up. Candace and Ginger glance at her. One of the Fireside Girls, wearing the brown and orange uniform, runs up to them.

"Good, you're here. You can help us with the search." Gretchen says.  
"Search?" Candace and Stacy ask in sync.

"Yeah, that big purple alien you guys fought–bravely I might add–left a few things here that Isabella has tasked us with retrieving." Gretchen tells them.

"Ugh, why do we care what happens to these things? Someone would just end up bringing them home and giving them to their kids or something anyway." Stacy says flustered.

"But these things could fall into the wrong hands." Ginger points out. Stacy scoffs at the sentiment.

"Fine. We can search for them," Stacy says with an eye roll.

"Great, we can go as one group," Gretchen says. They begin walking in the park.

Elsewhere in the park, Phineas, Isabella, Ferb, Buford and Baljeet walk around, looking at the various stands.

"Anyone spot anything yet?" Phineas asks.

"No, they could be anywhere by now." Isabella answers. They continue walking along, when suddenly a prominent gold-colored object, with an unmistakable ornate design, the helmet enters Buford's peripheral vision. He jerks his head to the side, small hands barely able to grip it.

Without hesitation, Buford storms up to the kid.  
"Give it to me." He demands.

"It's mine! I won it fair and square!" The kid proclaims, Buford rips it from him, the kid trips and falls on his rear.

"You can find something else." Buford says, walking back to the rest of the gang as they give him crooked stares.

"What?" Buford says, "it's not like we don't need it more." Buford says.

"Yeah…" Phineas says, he looks at the kid, seeing the wet eyes and a tear running down the cheek. At once, Phineas starts walking over to the kid. Isabella glances around, then begins tiptoeing behind him.

"Hey, sorry about the helmet but it's important we destroy it. How can we make it up to you?" Phineas asks.

"Are you good at throwing?" The kid pokes his head up at Phineas.

"You bet, what's your name?" Phineas asks, Isabella grins wildly as she looks at him.

"Frederick, and well, I really wanted this Ducky Momo toy, but I couldn't get it…" Frederick says with his head tilted down in somber reflection.

"That should be no problem." Phineas tells him. "Come on, let's go get it." Frederick walks in front, Isabella blushes profusely, her own feelings finding validation at every step they take.

They stop at a booth, Frederick points up at the Ducky Momo toy hanging from a ring.

"Here to try your luck at the 'moving ring of doom'? Top score gets you a one of a kind Ducky Momo toy," The attendant says. He grabs a ball, offering it to Phineas. Phineas reaches his hand out, before Isabella butts in.

"Ooh can I try?" she says quickly.

"Sure." Phineas says politely, handing the ball off to her.

The booth attendant presses a button, the rings begin moving. Isabella eyes up the top ring. With a wound up shot, the ball flings from her hand, landing square in the top circle.

"Yes!" She says, giving a declarative arm thrust.

"Nice shot Isabella," Phineas says cordially.

"Thanks Phineas." She smiles. The attendant hands her the Ducky Momo toy in all its fuzzy, bright-yellow glory. She quickly hands it to Phineas. Phineas turns to Frederick, handing down the Ducky Momo toy. Frederick gleefully takes the toy.  
"A thousand a one thanks! You're the bestest, kindest, nicest person I know!" Frederick gives him a passionate hug before running off. Phineas stares off into the crowd and sighs. Isabella looks at Phineas, then glances down sideways at the ground with a heavy feeling she can't pinpoint. She sighs, then looks back at Phineas.

The rest of the gang approach.

"We can't find that warhammer anywhere." Buford says.

"Perhaps whoever it was in that suit ran off with it." Ferb says. Phineas looks down, Perry laying there.

"Oh there you are Perry." Phineas says, picking him up. Phineas turns to Isabella.

"Maybe one of your Fireside Girls found something, Isabella?" He asks,  
"Let's see." Isabella whips out a phone and puts it to her ear.

"Girls, it's time to rendezvous in the center of the park." Isabella hangs up, and puts her phone away. They get to the center of the amusement park, they waddle around for a few moments before spotting Candace, Ginger, Stacy and Gretchen.

Gretchen walks up to Isabella, "I see you got the helmet," she says. Isabella looks over at Phineas.

"And a Ducky Momo toy…" She says in a coy manner.

"What?"

"Nothing." Isabella says as through the crowd, several other orange shirts and brown skirts appear, stepping out to join the group. Isabella turns to them.  
"Did you guys find anything?" She asks.

"We found two pieces of weird metal." Adyson, the one with straight brown hair says.

"That looks about right, great job girls." Isabella tells them. Holly–the Fireside Girl with dark skin and buck teeth–high fives Milly, who has freckles all over her cheeks.

"Nice!" Holly comments. Katie–who has pale skin, and blonde hair in pigtails–looks up at the sky.

"Cool, only one thing left for you guys to get." Candace says.

"Yeah, but that darned warhammer could be anywhere." Phineas says, his arm holding Perry is yanked, down, Perry drops to the ground and begins walking off.  
"Perry where're you going?" Phineas runs after him, the rest of the gang follow suit, rushing through the crowd. Their breath escapes faster and faster, until they come to a halt at the docks.

Perry leans towards the water. As the gang approaches him, he dives in, and swims to the bottom. Hidden from view, he springs into action, scoping with his bill, he finds the warhammer. He finds the gravity device he placed on it, deactivating it, he swims back up. Immediately after surfacing, he is scooped up by Phineas.

"Now what did you go doing that for Perry?" Phineas scolds him.

"Grrrrr," is all Perry can respond with. He turns around and walks to the water, Phineas catching him just before he leaps off the dock.

"Stop that!" Phineas shouts.  
"Hmm...perhaps he's trying to tell us something?" Ferb tells the group.

"Maybe..." Phineas says, looking at the water. "I know just the thing we need. Follow me, Ferb!" Phineas gestures. Him and Ferb run back into the mass of people. Isabella picks Perry up.

"Don't want you wandering off now do we?" She says. Ginger pets Perry.

"Who's a good boy?" Ginger says.

"Hey, is something up?" Isabella asks. Ginger looks at her, puzzled.

"What do you mean?"  
"Well, you're usually first to everything." Isabella points out.  
"True, I just slept in."

"You? Sleeping in, that's just…" Isabella begins to say, when she happens to look over her shoulder, seeing Phineas and Ferb back, hauling a big container, and a variety of dangling tubes.

"What's that?" Isabella asks as the drop it on the dock.

"A container that will atomize all of Thanos's gear in one fell swoop. And we have enough diving equipment for all of us." Phineas explains to her, her heart flutters as he offers her a set of scuba gear.

"Um, Isabella, you gonna take it?" Phineas asks. Her eyes widen, she looks down at the gear and back at him, quickly getting her hands around it.

"Oh yeah, thanks." She sheepishly smiles. Phineas turns around, seeing the rest of the gear gone, he looks at Ferb handing out the last one.  
"Wow, you're proficient." Phineas says.

"That's what brothers are for, so you don't have to spend ALL your time doing something as menial as handing out scuba gear."

"Good point." Phineas tells him.

"We aren't seriously going down there right?" Stacy asks.

"Yeah, my outfit isn't exactly made for water expeditions." Candace adds.

"Oh come on, we're going to need all of you here if we're going to retrieve the warhammer." Phineas pleads.

"Oh fine." Candace caves in. Stacy gives a pestered sigh, shuffling her feet along, she joins the rest on the edge of the dock. Perry watches on, laying down on the rickety wood boards near the atomizer machine.

"Three, two...one!" Phineas exclaims, they all jump on cue. The water splashes high, sprinkling Perry. In unison they swim to the bottom; elation mixed with utter angst comes over most of them as they spot the warhammer laying there. Phineas motions for them all to grab a side. The warhammer moves, but it quickly drags them down. "Push!" Phineas commands, every one of them in sync, lift and kick with all their heart. It moves closer and closer to the surface. They break the surface, a slight breeze moves past their shoulders. They lift the hammer above their heads, just nudging it onto the dock before they submerge again. Swimming back up, they grab hold of the dock, and pull themselves up.

They take off their gear.

"There, that wasn't too bad was it, Candace?" Phineas asks.  
"Well I suppose not." Candace tells him, half believing it herself.

"Now let's get it in the atomizer." Phineas encourages. They all grab it, straining their unworked muscles, they put the warhammer–Titan–into the case. They all let out a collective sigh.

"Well come on Candace, I think that's enough excitement for one day." Stacy says, waving her hand forward, believing Candace will come.

"What do you mean?" Candace asks with an inquisitive look.

"I don't want to be anywhere near this place or that thing." Stacy affirms. Candace sighs.

"But, we're just about done." Candace points out as the rest of the gang look at them.  
"Well no dice for me." Stacy says, Candace sighing as she looks on at Stacy walking away. The rest of the gang resume, putting the helmet and scraps into the atomizer.

Stacy's legs lock as a thunderous crash occurs in front of her. The sound of a helicopter motor peers through the boom. As the dust clears, standing tall before all of them, The Mad Titan, Thanos. He looks around at their petrified faces, he spots the equipment inside the atomizer.

"Well well, gathered it all...for...me." Thanos says, an explosion in the distance pierces their ears. Phineas, Ferb, and Isabella look down at the case at the exact same moment, they scramble to activate it. Thanos holds out his hand with a smirk, Titan develops an aura, smashing through the container, it returns to Thanos once again.

Thanos gets taken down to the ground, Titan flies up into the air, smashing hard against the ground. Phineas-1 extends a blade, thrusting it straight to the side of Thanos's neck. Thanos holds out his hand instinctively. The blade ruptures through it like a hot knife through butter, stopping just before the neck. Thanos holds out his other hand with a thunderous yell as Phineas-1 extends a blade from his free hand. Thrusting it at the side of Thanos's head, he is thrown off as Titan smacks him out of the air. The blade in Thanos's hand tears through the wrist Phineas-1 is thrown off.

Letting out a sharp yell, Thanos rushes to grip Titan with both hands. Phineas-1 charges at him with a blood-curdling yell, and blasted away just as viciously by an enormous blast of cosmic energy from Titan. Slipping Titan into one hand, Thanos turns to the kids with a maniacal grin.

Thanos walks unhindered about them, reaching into the shambled container, he pulls out the helmet. Chuckling then grinning, he puts on the helmet. He turns his back, beginning to walk away, he says with bated breath,

"Have fun with him." Nudging in the direction of the half of the park, devastated by the blast. He quickly vanishes from view. The moment of silence is broken by Stacy.

"Why!? Why us!?" She shouts loudly.

"That was too close!" Candace exclaims, breathing erratically.

Phineas walks past them, looking upon their frantic state with scornful eyes. Isabella, Ferb, Buford, Baljeet, and the Fireside Girls timidly follow. Candace and Stacy watch as the gang walk towards the point of impact. Candace calms her breathing, enough at least, to say,

"Come on Stacy, let's go with them."

"What? No! I'm staying right here where it's safe!" Stacy yells.

"Fine, be that way, I'm going to look after my brothers like a big sister." Candace proclaims, catching up with the gang. Stacy, left alone, looking at the ground, begins to sob.

The gang keeps walking throughout the scorched land. Phineas looks down, spotting a black leg. They take a few steps forward, some yellow to the black appears. He bends down, looking at the outline of the figure. He scans up to the black and yellow helmet. He looks at the strikingly familiar set-up with furtive appreciation. Looking on at the suited figure, Isabella and Ferb on each side of him, a foreign, longing feeling he's never felt before comes over him. Drowning it out, Phineas says resolutely, "let's get him home."


	3. Chapter 2

**This is my second chapter, it took a little longer than usual, but I got it done. Feedback is always appreciated if you can spare the time, so, without further ado, enjoy!**

Chapter 2

(Bold plays)

Phineas and the rest of the gang–with a lot of grunting–haul Phineas-1 up on the living room couch. Phineas takes a step back to look at Phineas-1's suit.

"You know what this reminds you of, Ferb?" He says.  
"The Beak suit." Ferb responds.

"Exactly, same yellow and black color scheme. Seems like we have a favorite color scheme no matter where we are."

"Suggesting he's one of us from another universe?" Ferb asks.

"Exactly…" Phineas says. Thinking for a moment, he presses his index finger on the side of the neck region of the suit.

The suit spontaneously morphs into a semi-liquid state, swishing about the air. The suit quickly solidifies, leaving a sight on the couch that doesn't elicit quite the reaction it ought to from the gang. A Phineas with the same general shape, but older, lies on the couch. Phineas-1, wearing blue pants, not unlike Phineas's own shorts, and a tan shirt with one orange stripe across it, akin to Phineas's tan shirt with four stripes. They look on in calm manners, their curiosity peaked more than anything else.

"What's he doing back here?" Ginger asks.

"We should wake him up, Ferb?" Phineas says, Ferb walks away, but quickly returns with a capsule. Placing it under Phineas-1's nose, his eyes start to flicker. Suddenly jolting awake, breathing frantically, his head darts around. His eyes come to a halt after spotting Isabella, causing him to enter a death-like stillness. Sparking back to life, he leaps off the couch, rushing to the door, he holds out his hand behind him, the suit flies to him and morphs around his body. He bolts through the door and goes airborne immediately.

"What was that about?" Phineas asks, glancing at everyone.

"Hmm...that suit seems marginally more advanced than our previous iterations." Ferb says.  
"You think?" Candace snarkily comments. Isabella turns to the Fireside Girls.  
"Alright girls, go out there and find that Phineas look alike while we come up with a gameplan, notify us as soon as you spot him." Isabella commands. The rest of the Fireside girls spring into action and run out the door.

_Meanwhile_

Thanos trudges up long stairs, his massive footsteps echoing throughout the entire stairwell. Eventually he finds his way to the top, pushing the door away with one hand, he walks into a hallway. Looking around, he spots a label that makes him smile–'Doofenshmirtz'–he approaches; he collapses to one knee upon reaching it. In frustration, he shatters the door with one punch.

"What in the world!?" Doofenshmirtz exclaims as the door breezes past him.

"Wha...who are you?" Doofenshmirtz asks.

"Names do not matter, make a device to fix me now." He says with bated breath, resting Titan against the corner.

"What makes you think I'd do that, I mean, you're in pretty bad shape but…"

"Want to be evil don't you? Make it!" Thanos barks.  
"Okay okay. I'll whip something up for you in no time!" Doofenshmirtz says with feigned enthusiasm. Thanos sits against a wall and glares at Doofenshmirtz as he gathers materials.

After some time, Doofenshmirtz says,

"There. It's done." Thanos gets up, pacing slowly around it, scanning it with his eyes, exploring every crevasse. He comes to a stop in the path of the ray.

"Do it." Thanos says, gritting his teeth. Doofenshmirtz hits a switch on the front of the device, it crackles to life, a ray ejects outwards and hits Thanos. The hole in his hand is filled in with new muscle, tendon and skin; the rest of his body experiences a vigor for the ages. Thanos grins, without missing a beat he walks up to Doofenshmirtz, and grabs him by the neck.

"Wha...what are you doing?" Doofenshmirtz voice strained as he's effortlessly lifted off the ground. Doofenshmirtz's voice hard pressed to come through with the massive hand enveloping his throat.

"You're no longer useful." Thanos says. His peripheral spots a figure, he looks to his side, on the building opposite, a man in a suit stands there watching. The man vanishes from sight. Thanos looks back at Doofenshmirtz.

"No!" Doofenshmirtz gurgles.

Thanos tosses Doofenshmirtz off the roof; he screams at the top of his lungs. Thanos begins walking to the ledge, summoning Titan to him. He looks down only to not see any kind of bloody mess that might be Doofenshmirtz. Thanos scoffs, then jumps from the building, crashing against the pavement with a thunderous boom. As the gravel sprays out, Perry lands with Doofenshmirtz on the balcony. "Grrr." Perry looks up at Doofenshmirtz with a stern stare.

"What?" Perry points to the device in response. Doofenshmirtz huffs.

"I had no choice, he was going to kill me." He says. Perry points at a utility cart, then to himself with a demanding growl.

"You want me to make you a suit? Okay I can do that. I can make one better than the last one by a mile, just you wait." Doofenshmirtz exclaims, bolting off.

_Flynn-Fletcher house_

"I...I don't get it, why would he be back? And why would he want to kill Thanos? I mean, he's an awful person but, death? He didn't do too much to him, I mean, you'd think I'd want to kill him for what he did to me and everyone else in the other timeline, but..I don't. I don't." Phineas says. Ferb listens closely, hearing every word.

"How about we try that quantum entanglement device again?" Ferb steers him.

"Excellent idea! Let's whip one up right now!" Phineas says.

Meanwhile, Buford throws rocks at part of the fence; Baljeet comes up to him, flailing his arms.

"Would you stop that!?" He says.  
"Um...no," Buford says plainly.  
"Why?" Baljeet asks.

"Simple. I'm bored."  
"Really? We find someone who looks just like Phineas, but older, and you're bored?"

"Yeah, it's happened before. I don't see what the big deal is." Buford shrugs.

"But all the possibilities are endless! What if it's him from another dimension yet again, though that would be cliche, or a clone created in a lab, or, if judging by the way he looked at Isabella, if he's…" Buford keeps throwing rocks against the fence for a moment before noticing the distinct lack of Baljeet's voice rupturing his ears.

"If he's what?" He asks, looking over at Baljeet, who stares at the fence with his jaw hanging wide. He suddenly snaps to.

"But that's mathematically impossible!" He says.  
"What's mathematically impossible!" Buford asks. 

Baljeet looks over his shoulder, seeing Phineas donning the headband. He runs to them. Ferb presses a button, the headband whirs. Phineas pauses for a second, then looks at his brother with a shaking of the head.

"It didn't work."

"Phew," Baljeet pipes in.

"What?" Phineas turns to him.  
"Nothing," Baljeet says quickly.

"No, that was something, but never mind that, we got to…"

"Guys!" Isabella shrieks.  
"What?" Phineas says, looking at her, startled.

"They found him!" She says.  
"Where?" He asks.

"He's just sitting on a rooftop downtown." Isabella says, folding up her phone. They're about to leave when Phineas notices Perry absent.  
"Where's…" Candace grabs him by the shoulders.  
"Come on now, worry about Perry later." She says, nudging him forward. They're just about to leave the yard, Candace stops and looks over her shoulder.

"Go, I'm just staying here." Stacy says.

"Really?" Candace says with furrowed brows.  
"Yes! Go!" Stacy tells her, she then turns around and runs after the others.

_Rooftop in downtown Danville_

Phineas-1 stares off into space. Putting his head back, he lets out a sigh. He closes his eyes. Meanwhile, Ginger slides her hand down the dusty rail as she shuffles up the stairs. She sniffles as the dust sprinkles her nose. She hears a voice behind her,

"Ginger, let's wait for the others." Gretchen says,

"Maybe he won't freak out if he sees us." Ginger says.

"No, let's just get back and regroup."

"I'm hardly important at all, he probably doesn't even know who I am. So we can use that to get close to him." Ginger explains.

"Fine, since you're so stubborn all the sudden." Gretchen relents.

Phineas-1 hears a rattling noise coming from the roof access door, he opens his eyes immediately. The door swings open, and out steps Ginger. Phineas-1 stands up, laying eyes on Ginger floods back all the memories that pierce his head like scolding hot irons, he stiffens on the spot, not moving an inch.

"We just want to help you, where are you from?" Ginger asks delicately. Phineas unfreezes, his boots rumble, as he flies off in the opposite direction, out of sight almost instantaneously. Suddenly, younger Phineas, alongside Isabella and Ferb, barge in. He looks around, then intensely glares at Ginger and Gretchen.  
"Why didn't you guys wait for us?" Phineas asks.

"Well I thought…"

"Ginger and Gretchen you were told to wait, why didn't you!?" Isabella yells past Phineas.

"It was her idea." Gretchen points to Ginger.

"Uh uh, you knew better too, I'm disappointed in you girls, you should have listened to me!"

"He froze last time he saw you, I figured we'd have had a better chance."

"And did you?"

"I got a word in." Ginger says, crossing her arms. Isabella gives her a scolding glance, Phineas begins walking around in circles.

"I'm out of ideas on how to find him." Says Phineas bewildered.

"Maybe we just leave him to do his thing, he clearly doesn't want to be around us." Candace says.

"That May be true, but it's not right." Phineas retorts.

"We don't even know his story." Candace points out. Ferb interjects,

"true, but in the end, does it really matter?" After a bout of silence, Candace mutters,

"I mean, I guess if I'm outvoted on this matter."

"Wait a minute, we need to go back to the carnival!" Phineas exclaims.

"What, why?" Candace asks.

"We left some important things there, we should go back there and gather them." Phineas explains.

"Sounds good." Ferb says.  
"I'm up for it." Isabella chimes in, she turns to Ginger and Gretchen.

"Ginger, Gretchen, tell the rest of the Fireside Girls to rendezvous at Phineas's house."

"Aye aye" Gretchen salutes, then walks off. Ginger drags herself behind as they enter the stairwell.

_Streets of Danville_

Cars honk their horns louder with every step the Mad Titan takes. Thanos looks at one he happened to be next to, aims Titan, it charges with cosmic energy, then blasts the car. The blast shreds it to pieces. Shrapnel strikes every windshield on the block, pieces that hit Thanos bounce off. Walking forward, Thanos looks down at his healed hand, he clenches it. Looking towards the right, a mound in the distance, a crossroads. Grimacing, he shakes his head, looking towards the left and turning.

_Doofenshmirtz Evil Incorporated_

"There." Doofenshmirtz says, putting the welder on the utility cart. Perry gives the thumbs up. Climbing into it, the suit mechanically morphs around Perry, layers of plates sliding on top of one another, with just a tiny amount of space. Perry moves his arms freely, miniature missile slots come out on top of the wrists. Using the HUD, Perry sheaths the missiles, then flies off.

_Carnival grounds_

The gang head to the docks. Phineas spots a crimson substance, teetering on the edge of the bay, drying on the even dryer pavement. Candace passes him, carrying a baggie with two scraps of The Mad Titan's armor. He catches up with them slowly, walking through the scorched grounds.

His feet stop in their tracks when he notices something out of the corner of his eye. Half of a fluffy Ducky Momo toy. He walks over to it, some ash sprinkling the fur. He picks it up, some of the ash trickles to the ground. He stares at it some more, tilting his head slightly.

_Streets of Danville_

Thanos looks up, seeing a rollercoaster in the foreground, he chuckles. A few steps later, he is rocked forward, Phineas-1 dropping on top of his head, a blade pointed straight down at it. Titan launches up, knocking Phineas off; he gathers himself as Thanos turns to face him. A massive series of explosions rock the pavement, Thanos trips, and drops to the ground like the biggest sack of potatoes. Phineas drives a blade down, the handle of Titan is shoved in the way, a resonating ting goes off, neither metal budge. Phineas slides the blade backwards, Thanos jerks his head to the side, the blade goes through the concrete with ease, the edge almost touching Thanos's helmet.

Thanos launches to his feet, Phineas stares at him, blades extending from both his suit's wrists, Perry hovering by his side. Phineas looks at him.  
"What are you doing here Perry?" He says. Perry glances at him then, returns his gaze to Thanos.

"One loyal pet, but that matters little." Thanos says as he charges in with a yell. A swing of Titan sends Phineas hurdling into a building, brick dust darting through the air.

Thanos swings Titan at Perry, who dodges it, as well as a blast of energy from the other hand. He launches at Thanos's face; a simple headbutt knocks him away. Thanos smiles gleefully. He takes a step forward, angling his torso to the side as Phineas bursts out of the building. Thanos swings Titan, it crashes into Phineas, sending Phineas flying far forward into the distance. Thanos leaps after him.

_Carnival_

Phineas looks to his side, the rest of the gang having disappeared. He looks back down at the ducky momo toy in his hand.

"Can't be...Frederick's still alive right? He's got to be…" He sighs, he tosses what's left of the toy behind him in fury. He faces forward again, looking down at the ash. Suddenly a huge crash ripples behind him. Phineas jumps, turning around to see gravel spirals upwards into the air. When the dust clears, he sees Phineas-1 lying there.

Instinctively, Phineas runs up to him. He hears a boom from behind, turning, he sees Thanos standing there. Titan charging in his grasp. Phineas-1 wakes up, looking past Phineas, he flies up to charge at Thanos. Thanos smiles widely, throwing Titan in all its might straight ahead. Phineas tries to cover his face; Phineas-1 looks down just to see the nefarious warhammer smash through Phineas, blood splatters all over. Phineas-1 rocks in his armor, every ounce of his being recoils, then rebounds into righteous fury.

"NOOOO!" Phineas-1 shouts, charging straight for the madman's heart! Thanos blasts him right through the ground with his fist. Phineas-1 plummets past sea level. The loose ground falls on top of him. Water floods in through the cracks. Thanos walks forward, placing a hand in the fresh blood, He walks away, in the direction of the hill, Titan returns to him, dripping water. A smile plastered on his face. The last half of the ducky momo toy, soaked in fresh blood, and old ash, topples down into the hole.


	4. Chapter 3

Chapter 3

(The Unattainable)

Thanos places his blood soaked hand on the dirt, and gets up. He looks ahead, waiting. Before his eyes, a figure appears, dressed in a suit.

"To what do I owe the pleasure?" Blackheart asks.

"You've been watching me." Thanos says. Blackheart cackles.

"I have, most impressive." Blackheart explains.

"I'm no fool." Thanos tells him.

"And yet you contacted me..." Blackheart says.

"For what purpose have you spied on me?" Thanos inquires.

"Mephisto willed it."  
"And you serve your father? I can see it in you Blackheart, you don't want that." Thanos says.

"Indeed, but why would I ally myself with you?"  
"Mutual advantage, we get rid of my adversary, and we can get rid of Mephisto once and for all.

"I'll think about it..." Blackheart vanishes. Thanos chuckles.

Meanwhile Phineas moves his head, shifting some debris. His eyes flutter open, looking around, gravel thrusts itself at him in every direction. He moves around, then flies upwards, bursting out from the hole in no time. The moonlit sky shining against his armor. He lands next to the drying blood pile.

"I…" His words stop there, his head twists and turns violently, he stabs the ground repeatedly with his blade, yelling all the while. Tears flow out of his eyes, his vision distorts. He forces himself up.

He looks at the pile, he grits his teeth, shakes his head, and flies off. He flies over the city, building after building, trying desperately to clear his mind to no avail. Eventually, he finds himself in the neighborhood of his childhood, that fact that it could become so accursed once again, is enough for him to steer far away from it. But a certain compulsion in the far corners of his mind brings him here.

He sees a house he recognizes all too well, he taps the top of his wrist, causing his thrusters to go silent. He hovers down to the side, a large window there. A bed inside, a dog bed nestled against the front of it. Isabella sleeps with her back to the window. Part of her black hair draped slightly over the side of her cheek. Small in and out breathing making the strands rustle. To stare at her so, he recoils. But nothing else he could see himself doing right now, his heart heavy, heavy enough that it feels like it'd drop straight through him.

Suddenly, barking alerts him, the small chihuahua faces him, yapping as fast and as loud as he can. He goes to back away slowly, he looks up at the bed to see Isabella's eyes trained on him, he rushes to get away, clearing the neighborhood in record time, finding some rooftop to crash on. His helmet retracts, exposing his face to the gentle breeze. His breathing becomes frantic as his thoughts race. He tenses up, he looks up at the sky. Eventually, he calms enough to not notice as he slips off into sleep.

Over a Month Ago...Previous Timeline

Phineas awoke on the cold, metal floor. With his cramped right shoulder, he pushed himself up and walked off to the elevator. The elevator went up. It came to a halt as a panel slid to the side, revealing small erect stone slabs embedded in the grassy yard. Phineas's attention was drawn to the house as the door exiting to the backyard swung open. Baljeet stormed out, for a moment their equally pale eyes met. Baljeet walked past him, pressed on the trunk of the tree, then stepped into the elevator.

Phineas walked to a part of the fence, pulled out a device from his pocket and put it against the tanned picket. After reading '100%' on the screen, Phineas put the device away.

"Is the fence still up and running?" Asked a voice from behind.

"Yeah. It'd vaporize just about anything when the current connects." Phineas said with a suppressed smirk. He turned to face Ginger, her dark brown eyes locked on to the fence.

"Since we're all up, we should go over the plan again." Phineas began to walk to the tree.

"I think I'm going to tend to the graves..." Said Ginger, looking down, gripping her wrist. Phineas turned to look at her in confusion.

"We need you when we go over the plans; what's the use if only two of us know?" He told her.

"Baljeet refuses to talk to me anyway." She said with a scoff.

"That's it? You won't review the plan with us over hurt feelings?" He said to her, irritated.

"I guess so." Said Ginger defensively.

"Fine." Phineas said. He walked to the elevator while Ginger stopped at a grave, Phineas looked over his shoulder to see her mournful demeanor as she stared at one of the graves.

Phineas descended into the lair, and walked over to Baljeet. Baljeet turned to him, then back to the monitor that contained a multitude of diagrams, some city wide, some planet wide. A separate screen attached to the monitor showed 100% functionality in the list that expanded far past what could be shown at once.

"When will my suit be ready?" Baljeet asked Phineas. Phineas scratched the back of his head as his face muscles twitched slightly.

"It's hard to get the material for it, but as soon as I do you'll get one."

"Okay, fine, but I better."

"Let's go over the plan one more time." Said Phineas eagerly.  
"I'll be sure to activate the field around the earth as soon as he shows up, that will dampen his powers enough to give us some amount of a fighting chance. If things start to go awry, we retreat back here. And if he shows up here, we do it in reverse."

"Still don't want to iron out any of the holes?" Asked Phineas.

"The gauntlet is too much of an outlier to account for. As I've said before, every single time you've brought it up, we'd be wasting our time better spent elsewhere." Said Baljeet. "Seriously, all the monotony, we aren't even living."

"Starting to sound like Ginger there." Phineas said.

"Oh don't even get me started on her. She wanted to get serious." Baljeet scoffed as he said it. "Can't afford that kind of distraction."

"Who says it's a distraction?" Said Phineas.

"Me. Killing Thanos is what matters. After he's dead...then...maybe."

"Is not talking to her really the best way?" Asked Phineas.

"Yeah, clearly she doesn't get the message any other way. Now can we stop talking about it?" Baljeet asked loudly.

Phineas walked to the elevator, and exited the lair. He headed into the house, the noise punctured his eardrums. Most of the rooms' walls taken apart, filled to the brim with machinery. Phineas looked around, first he knocked on the bathroom door, he turned the knob, nothing there as the light flickered on. He closed the door, and went up the stairs. He entered the other room which contained a small window for overlooking the backyard. Faded purple carpet lined the floor, again, no one other place in mind, Phineas walked out the front door, and headed down the block behind his house.

He stopped at a door. He opened it. The inside aroma shocked Phineas. It's simple and semi-elegant nature brought his mind back to the times he'd long forgotten. The carpet was cleaned, the counters were in pristine condition, the sofa free of excess lint. He walked past a baron shelf, the only place with dust on its surface. He walked into the hallway, a door opened as he took a few steps forward, and out walked Ginger.

She jumped slightly.

"What brings you here?" She asked.

"Just wanted to see if you were alright. We need everyone together, not apart." Said Phineas. Ginger looked at the ground at an angle as she fiddled with her hair. She then turned her gaze to him.

"That's more than Baljeet cares to." She said.

"He doesn't always reliably process things. I wouldn't judge him too harshly." Said Phineas. Ginger eyes went wide, then slowly narrowed.

"Really?" Ginger said as she slowly approached Phineas. Her heart fluttered as she closed in on him. He looked at her blankly. She grabbed his shirt softly, and kissed him on his lips. She pulled alluringly away, leaving him to make the next move.

His mind raced to consider the course of action, but his body's impulses were already ahead of him. His hands planted themselves on her hips, his mind blanked. As control was taken by base desires, he returned her kiss with a kiss of his own.

She leaned herself against him, and delicately wrapped her arms around the back of his head. As their lips are locked, and their eyes shut, Ginger guides both of them to the room she'd just left. She dragged Phineas to the bed, laid herself down, and pulled him slowly. He pulled away. "Wait…" He looked at her in the eyes, seeing her stare at him with such yearning, he paused, then continued. "We shouldn't...it isn't..." She put her finger over his lips.

"Shh...Just enjoy this." She said, and pulled him closer. Their lips locked again as Phineas's arms wrapped around her back. As they continued kissing, Phineas's hands moved to caress her head and hair. She grabbed them, moved them down slowly, and pressed them against her breasts as they continued to kiss each other.

Later, Phineas was sat up in her bed looking at the clothes strewn on the floor, his intermingling with her's was worse to him than kicking a disabled puppy as it crawled joyfully to its owner. His breathing quickened, he escaped the bed, took his clothes and put them on with each step he took. He had returned to his backyard. A gravestone with the words 'Isabella Garcia Shapiro' on it came into his field of vision. He fell to his knees in front of it.

"I'm just a shell of the boy you loved, the one who couldn't see a damn thing." His forehead rested on the top of the dry, grainy stone.

"You deserved better, you DESERVE better. I'll do right by you if it's the last thing I do. I'll do right by everyone..." That last word–_everyone_–hung with him, a broad word, in his heart, broader than the entire universe could ever be.

Present Day

Phineas jolts awake, he leaps to his feet and flies off. The sun beating down on his armor, he flies past a rollercoaster, and lands where a puddle of dry blood is. He gets down on his knees, and puts his hands together.

"Oh Mistress Death, reaper of souls, I beseech thee, hear my call, and answer my prayer!" Phineas opens his eyes, he looks around, everything the same. He yells and strikes the ground, cracking it.

He flies up past the rollercoaster, looking down, the ground becomes pitch black. Suddenly, stone manifests below his feet. He plants his feet on it. He walks forward, the darkness departs slightly, revealing a throne in the center. A robed skeleton sits there.

"Speak." The voice, guttural, and feminine, pierces into his being.

"I'm here to learn what happened to a young boy who was...murdered recently." Phineas says, whether he was prepared for it or not.

"I know of it, but I can not help you. Your younger self was not claimed by me." Phineas darts his head up at once, looking straight at her.  
"Who then?" He asks.

"Mephisto." Mistress Death tells him. Phineas steps back.

"What!? How!? Every soul goes to you, unless they make a deal with another entity. Phineas didn't." Phineas tells her.

"But you did. And he shares your soul. He was forfeit right from the start." Mistress Death explains.

"I...No. No no no no no!" Phineas shakes his head.

The environment turns to normal; at once, he starts falling through the air, he engages the thrusters and hovers.

Phineas grabs onto his helmet, he squeezes and yells at the top of his lungs.

"I can't do this!" He shouts. "I…" He looks ahead in the direction of his old neighborhood. "I don't have to..." He takes a gulp of air, his breathing comes more erratic as the thoughts enter his mind. He lets out a primal yell, and blasts forward. He heads straight for his old house. He finds it, flies over the roof, and lands in the backyard. He looks forward to see everyone staring right at him.

Putting his hands up, he takes a giant breath in, his cheeks spasm. He steps out of the suit. He tries to speak, but all he can do is stand there as all their eyes are fixated on him.

"Why were you watching me last night?" Isabella points at him. Phineas takes in another deep breath, slowly exhaling as he turns to look at her. He then turns to look at Ferb.

"Your Phineas has been trapped in another dimension and I need your help to create a portal so I can rescue him. I know the coordinates."

"That can be done." Ferb says, Phineas nods.

"Uh hello, why were you outside my window?" Isabella asks. Phineas sighs, before looking back at her with a heavy heart.

"I just wanted to make sure you were safe. Your phineas is trapped in the same place I came from, I need to save him." He says.

"What do you mean, make sure I was safe?"

"Thanos is out there. I know you have a history with him. I wanted to make sure he didn't get to you."

"Why did you freeze when you saw us earlier?" Isabella inquires.

"I just wasn't used to seeing you guys aga...I mean, this way."

"This way?" Isabella asks.

"Yeah, you know...younger."

"It's ready!" Ferb shouts out, Phineas immediately leaves the conversation, he uses a panel to enter the coordinates. The portal booms open, a heavy mass of red pulsates from within.

"You came from there?" Isabella says, recoiling from the sight. Phineas steps into it, the portal crashes from the other side as he collapses on the molten rock.

Phineas gets up, and takes in the sight before him, he engages his thrusters, hovering just above the ground. Demonic structures dot every inch of the landscape.

"Phineas…" Phineas hears echoed from every nook and cranny at once.

"Mephisto, I need a favor!" He shouts, Mephisto appears before him. His figure, tall and red, with a cape that seems a part of his form draping behind him.

"What favor is that?"

"You recently acquired a soul, exactly like mine. You know what I'm talking about?" Phineas asks.  
"Oh yes...It is yours in every manner, though not as juicy. And certainly less alive right now." Phineas bites his lower lip before speaking.

"I need him back."

"Why?" Mephisto inquires.

"He…" Phineas looks down for a second, then looks back up. "He's instrumental in stopping Thanos, I need him if I'm going to do it." Phineas explains. Mephisto cackles.

"Since you'd refuse any alternative, and I couldn't accomplish my mission without you...FINE." Mephisto says, and with a wave of his hand, Phineas plummets down. Suddenly, the blue sky lies above him.

He gets up, seeing the wreckage of the carnival before him, he hears a slight rustle behind him, he slowly turns around to see younger Phineas standing there.

"What...what happened?" Younger Phineas looks around confused.

"Hold on, it's alright, I'm bringing you home." Phineas grabs his younger self, and blasts off, not hearing his younger self's cry of "Wait!"

He drops down into the backyard, the portal device gone, he puts younger Phineas softly on the ground.

"I…" Younger Phineas begins to say, suddenly he is hugged from behind by Isabella. Phineas looks down at this, and...something most foreign flashes on his face, a smile. Momentarily able to be a viewer in someone else's story. He feels something in the moment he thought lost long ago...happiness.


End file.
